SiFive's RISC-V HiFive Unmatched Upgraded To Ship With 16GB Of RAM

[Viki Ai]

Why did they drop ecc ram? (I am assuming they did because I am only counting 8 chips)

[CTown]

Thanks brucehoult for that info. I have been trying to search which Arm processor core the U74 matches up with.

If it is a desktop board, it is pretty shitty, because it only has 4 cores, mean while Intel and AMD have more on their desktop boards. Also for a desktop board, it is expensive.
If its a dev board, its pretty shitty, because its homogenous and only has one core, not small cores and big cores.

You need to put things into perspective. It's about the progressing of this open technology. AMD and Intel have only been releasing consumer hexacore processors for 10 years [1]; on an architecture that came out in the late 70s (if you count the old 16bit days). It was only with the Ryzen 1600 that the hexacore processors got cheap enough for the general public. That was only a few years ago. Look at this quote from PCMag [2]:

Six cores and 12 available computing threads for not much more than $200: That's what AMD's Ryzen 5 1600 processor is all about. And on paper at least, it's a very appealing proposition when you consider Intel's similarly outfitted six-core Core i7-6800K costs about twice that much ($440 or so, when we wrote this in late May 2017).

[1] https://www.zdnet.com/article/intel-...desktop-chips/

[2] https://www.pcmag.com/reviews/amd-ryzen-5-1600

[brucehoult]

If it is a desktop board, it is pretty shitty, because it only has 4 cores, mean while Intel and AMD have more on their desktop boards. Also for a desktop board, it is expensive.
If its a dev board, its pretty shitty, because its homogenous and only has one core, not small cores and big cores.

This, and many of the other messages here are just ridiculous.

No one -- certainly not the manufacturer -- claims that this is a competitor for PCs using chips from Intel or AMD.

As recently as four years ago there was not yet a single shipping RISC-V CPU in the world (the HIFive1 shipped on December 20, 2016 and I received mine in Moscow in early February), and RISC-V pioneer SiFive had about 15 employees. By early 2018 they had about 30 employees, and have grown quite a bit since then, but they're still very small, very new, and have massively less funding when compared to Intel, AMD, ARM, Qualcomm, Nvidia that any such comparison is ridiculous.

As with the dozens of other RISC-V companies that have sprung up since then, most of SiFive's business is in microcontrollers. They're supplying the controller for the 5G radio and the camera in Samsung's current high end phones, controller for the 5G radio in current Qualcomm chips, the main/only SPU in the latest ESP32-C3 WIFI/Bluetooth chip from Espressif (and one of the two CPUs in the ESP32-S2), the CPU in the new Bouffalo WIFI/BT chip, the CPU in super long battery life Amazfit watches, etc.

SiFive is in the lead for pushing RISC-V to higher performance CPUs and the FU-740 in this board is by far the most powerful RISC-V CPU offered for sale to the public so far. The U74 cores were announced two years ago, in late October 2018, so they are right on time for the usual 2 to 2.5 years from announcement of a core to being available in chips and products you can buy. ARM cores have a very similar time between announcement and product availability.

SiFive and others have announced more powerful cores -- including SiFive's Out-of-Order U84 that was announced 13 months ago. Those will no doubt start shipping in products in another 12 or 18 months.

The U74 is pretty much equivalent to ARM's A55 core, announced May 28, 2017 i.e. 18 months before the U74 was announced. It's definitely significantly better than the A53 found in the Raspberry Pi 3 and 3+. It's not as good as the A72 found in the Raspberry Pi4 (the U84 is about the same as the A72). The main difference is that those ARM chips have NEON SIMD, which the current RISC-V cores don't. But RISC-V has a upcoming Vector extension which is far better than NEON or AVX. The first cores including it were announced in September and October, from SiFIve, Andes and others. They will be shipping in products in the usual 2 to 2.5 years.

In real use the HiFive Unmatched will probably be close to a Pi 4, or even better, as it's not running off an SD card but a proper M.2 SSD, has more and much better RAM, PCIe, can take a real discrete GPU (Radeons are supported) and so forth. It's probably better to compare it to a Pentium III or PowerPC G4 from around 2001 except that, again, it's got much better and more RAM and I/O -- as well as being 64 bit not 32.

The closest comparison might be to a low end Core2 Duo, such as the original MacBook Air. Or a few years old Atom.

The point of this board is that it's the first RISC-V board that allows real dogfooding -- allowing people who are developing RISC-V software to do it on the actual machine they are writing the software for, using it as the development computer itself.

As such it's pretty much irrelevant whether the price is $100 or $600 -- the difference is a days salary.

When all software is in place and things go into mass production for normal users to buy -- maybe with a U84 core with a Vector processor added -- the price can be much lower.

[uid313]

This is a desktop board; there is no need to switch from four "small cores" to four "big cores". I know I have not been following up on HiFive but do they even have more powerful cores than the one included on this board? If they do, they might not even price them in this board's price range.

If it is a desktop board, it is pretty shitty, because it only has 4 cores, mean while Intel and AMD have more on their desktop boards. Also for a desktop board, it is expensive.
If its a dev board, its pretty shitty, because its homogenous and only has one core, not small cores and big cores.

[jaxa]

One of the biggest factors to lend immense credibility to RISC-V is Arm Holdings' bailing out of their, up-til-now, cash cow.
(The question no one ever asks is, "Hey, if this thing is making them SO much money, why do they want to sell it?"; or, "If this person is SUCH a flaming genius at investing and making money (real estate; stock market...), why are they on TV trying to sell me a course on how to make money? Isn't their time worth more than trying to sell me a chintzy course on...?)

https://tech.newstatesman.com/busine...vested-in-firm

https://www.reuters.com/article/soft...-idINKBN22U0KM

“The coronavirus is an unprecedented crisis,” a notably downbeat Son told an earnings presentation, comparing it to the Great Depression.

Appearing far more subdued than usual, Son said some of his tech unicorns had fallen “into the valley of the coronavirus”.

“I believe some of them will fly over the valley,” he added, standing beside a slide depicting cartoon unicorns dropping into a hole as a lone winged unicorn escaped to the other side.

The crisis has pushed the Vision Fund’s portfolio underwater, with its $75 billion investment in 88 startups worth $69.6 billion at the end of March. The $100 billion fund had already delivered two consecutive quarters of losses before being upended by the outbreak.

SoftBank went into panic mode this year because a lot of their Vision Fund investments did not respond well to the coronavirus. Arm is not unprofitable, it's just that its value hasn't increased much.

[sandy8925]

This is a dev board, not a productivity workstation. Besides, it was only in 2017 when *all* of intel's top Core i7 chips were 4-core. There's not much of an ecosystem out there for consumer software that can leverage more than 4 cores right now. Again, plenty adequate for a dev board like this.

Consumer software does benefit greatly from increased core count, you forget that people often have multiple applications and programs running at the same time. Well-written everyday software uses multiple threads for all sorts of work (UI/input, networking, IO, compute etc.)

[duby229]

I don't have much knowledge in the area of CPUs, what sort of benefits/drawbacks come from an OoO cpu vs an in-order cpu?

Mark Rose explained it well, but also IO sensitive loads run with much better latency on OoO architectures. From an end user perspective OoO processors "feel" much smoother.

[CTown]

...Yes, 4 cores is very little. Pretty much all phones have 8 cores, even the cheap ones. All or most of the Snapdragon series of SoC from Qualcomm have 8 cores. The Apple A14 have 6 cores. 4 cores is little, you could buy phones many years ago with 8 cores.

This is a desktop board; there is no need to switch from four "small cores" to four "big cores". I know I have not been following up on HiFive but do they even have more powerful cores than the one included on this board? If they do, they might not even price them in this board's price range.

[danmcgrew]

Isn't it amazing that all the cheap shots against RISC-V, by Arm Ltd. (or Arm Holdings) stopped coming when Arm's sale to NVIDIA became a 'thing'. What's that saying (by Ghandi, I think)?--
"First they laugh at you. Then they fight you. Then you win."
Arm did a lot of laughing.

One of the biggest factors to lend immense credibility to RISC-V is Arm Holdings' bailing out of their, up-til-now, cash cow.
(The question no one ever asks is, "Hey, if this thing is making them SO much money, why do they want to sell it?"; or, "If this person is SUCH a flaming genius at investing and making money (real estate; stock market...), why are they on TV trying to sell me a course on how to make money? Isn't their time worth more than trying to sell me a chintzy course on...?)

It seems as though Arm just might have seen (the) 'handwriting on the wall'. AND decided that selling was a much better option than Ghandi's second; fighting.

[Not sure what the current state of the NVIDIA takeover is; last I heard (in November), some very high-level financial type had thrown a monkey-wrench in the works. Comments, anyone?]

[Alexmitter]

Which parts of the hardware is open source?

From a 2 min search I found that the SoC is a "FU740" which uses "Core IP 7". Do you know how much of this is actually open source and do you have links to the code?

I'm concerned that Si-Five will be a defacto RISC-V standard which will just be an ARM in sheep's clothing. Hoping that I'm just being stupid/paranoid here.

Found this list useful: https://github.com/riscv/riscv-cores-list

Risc-V is a instruction set specification that is open. That does not mean that the core design a certain company develops is also open. Non the less, there are open core designs available for the general public.

With ARM, you pay to license the instruction set and you pay to license a core design if you do not want to develop your own.
With RISC-V, you pay nothing for the instruction set and, if you do not want to design the core IP block yourself, you can license one from a company like SiFive.

Core IP blocks and the instruction set are two very different things.